For what it's worth i grew up where there were no leash laws, dogs came and went with few problems. I've never had to shoot a dog in defense. I've smacked on or two. I've been nipped plenty of times, clawed by cats, etc.

I know an aggressive dog when i see it. As i said, hair standing up, ears and tail up, showing teeth and charging. It was not even in a defensive posture.

Funny thing is my hand went to my pocket knife first. I remember thinking "hey stupid, other pocket"

I didn't even flash anything. but if the dog went off the leash, i'd have been forced to take care of it. Though i would have ended up bit, a dog can clear 10' very fast. I was ready to give it my left forearm to chew on, i was wearing my company jacket anyways.